J4MEJ4ME (Java For Me) is an open source library to help build J2ME applications

AlgoMo (Algolight Mobile)Algolight is a programming language that can be used to implement simple mathematical algorithms that operate on variables, vectors and matrices, and includes controls for loops, while loops and if / else structures. The program can also be used as a simple calculator, it supports some trigonometric functions, roots, and logical expressions and relation symbols

Geek toolsGeek tools - Features:
Prime number checker: Can check a 64-bit integer for primality.
Al bhed translator: Al bhed is a language spoken by a race in the game Final Fantasy 10. This tool allows you to convert from Al bhed to English and vice versa. The code that does this is very generic so it could be done to any other language and I am open to suggestions. Eg, Elvish

MID4thMID4th - MID4th is an adaptation of WebForth for mobile devices. Program in Forth and time warp back to the eighties. The system supports persistent block sets, and it is possible to develop on the device itself. I have added some features for text entry to help with limited keyboard handling within MIDP-2.0

PhoneGapPhoneGap is an open source development tool for building fast, easy mobile applications with JavaScript.
If you are a web developer who wants to build mobile applications in HTML and JavaScript while still taking advantage of the core features in the iPhone, Android, Symbian and Blackberry SDKs, PhoneGap is for you

Youtomo - Mobile Web BuilderYoutomo - Mobile Web Builder - free service for creating mobile websites that work well and look good on all mobile phones.
This service is primarily designed for small and medium size enterprises wanting to promote their products and services and to interact with their customers on the mobile platform

J2MEGLJ2MEGL - The J2MEGL (Java 2 Micro Edition Game Library) is a high-customizable library to speed up the development process involved in games when dealing with repainting, sprites and movement.
It is based on the MIDP-1.0 specification

zmobileZmobile is an open source library to help build J2ME applications

Libsssd 089m_20050905Libsssd is a cross-platform, integer-based audio library designed for interactive applications and games on small devices such as smartphones/PDAs
Libsssd currently supports Linux (OSS, ESD), Win32, WinCE Intent/AmigaDE (hosted), and Symbian S60